With the concept of “humanized lighting” deeply rooted in the hearts of people, the lighting design should create a good indoor lighting effect to meet people's physiological and psychological needs. Now more and more lighting design uses LED lamps, and at the same time LED lamps also begin to replace the original ordinary lamps, such as fluorescent lamps, halogen lamps, fluorescent lamps and so on. But because of its characteristics LED lamps, people must convert electric supply to low voltage DC current. Therefore, the assembly of the entire LED lamps often include DC power and LED lamps. As quality of life becomes higher and higher, controllers may sometimes be added between the DC power supply and the LED lamp to complicate the installation of the entire LED lamp.
These DC power supply output voltage is usually low, the output is difficult with the sustained high pressure during the installation of the project or during the test, the input and output are occasionally reversed, the output is wrongly connected to the high voltage mains. At this time, the DC power supply is damaged, and uncontrolled high current flows through the components in the power supply, which may cause fire accidents.